This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We had a number of meetings to decide topics that we might develop into program projects. Because the metabolic syndrome is a major public health problem, and NASH (non-alcoholic steahepatitis) is a component of this syndrome, we decided to examine factors that might contribute to this phenomenon. Therefore, we have designed four experiments to investigate the circadian rhythm, various genetic backgrounds (strains), various diets, and ages (old) of mice. We have collected the tissues of three of these experiments.